Hi Wojciech,

Thanx for the pointer - you helped me find the problem.  In my application
(when it did work), I wrote some parameter data to PortB - when I checked it
with my Logic Probe, I couldn't understand why it wasn't being driven (I
cleared TRISB).

I should have looked more closely at the documentation.

While it would never boot with RB3 tied to ground, I added the parameter:

"_LVP_OFF"

To the "__CONFIG" statement and the 16F877 runs fine now.

I think this little hint will end up on my web page.

Thanx to everyone else who replied.

myke

----- Original Message -----
From: Wojciech Zabolotny <wzab@ise.pw.edu.pl>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Thursday, September 23, 1999 10:06 AM
Subject: Re: PIC16F877 unreliable start up


> On Thu, Sep 23, 1999 at 12:59:52AM -0400, Myke Predko wrote:
> > Hi Folks,
> >
> > I've been playing around with a sample 16F877 and I am having problems
with
> > not getting a reliable start up.  I'm trying to run it at 4 MHz (using a
> > crystal and two 15 pF caps).  The operation of the oscillator seems to
be
> > hit or miss (mostly miss).  I've played around with different parts
(I've
> > tried a ceramic resonator, different values for the capacitors) and
still
> > nothing that is reliable.  I have not tried an in-line resistor.
> >
> > Has anybody else seen this type of problem and if you did, what did you
do
> > to fix it?
> I'm not sure if entering the programming mode may affect the oscillator,
but
> is the RB3 pin floating? If yes, tie it to the ground.
> --
>                                 Greetings
>                               Wojciech M. Zabolotny
>         http://www.ise.pw.edu.pl/~wzab  <--> wzab@ise.pw.edu.pl
>
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